Laminating press



May 3, 1966 A. w. SALTER, JR 3,249,136

LAMINATING PRES S Filed Aug. 26, 1963 3 Sheets-Sheet l INVENTOR.

ANDREW! SIZTER, JR.

J W WM A TTORNEYJ y 1966 A. w. SALTER, JR 3,249,136

LAMINATING PRES S Filed Aug. 26, 1963 3 Sheets-Sheet 2 I NVENTOR. ANDREW M. 5/41 TEE JR.

m ATTORNEYS May 3, 1966 Filed Aug. 26, 1963 A. W. SALTER, JR

LAMINATING PRESS 5 Sheets-Sheet 5 INVENTOR.

AVA/DREW n 5141 TER JR United States Patent 3,249,136 LAMINATING PRESS Andrew W. Salter, Jr., Tucson, Ariz., assignor to Jiffy-Dol- C0. Filed Aug. 26, 1963, Ser. No. 304,494 Claims. (Cl. 144-283) The present invention pertains to laminating presses, and more specifically to laminating presses particularly useful for laminating thin veneer on continuously curved wood surfaces.

The prior art includes a wide variety of laminating presses including presses intended for the lamination of wood such as plywood. However, none of the presses of the prior art are suitable for the application of a thin veneer to a continuously curving wood surface. The application of veneer to such a surface presents problems which prior art laminating presses are unable to solve. When the application of thin hardwood sheets entails the cementing of the hardwood to a curved wood surface such as a door frame of the type described and claimed in my co-pending application Serial No. 152,768, filed Nov. 16, 1961, now Patent No. 3,119,156 issued on Jan. 28, 1964, the application of even pressure to all portions of the hardwood sheet and supporting soft wood structure becomes an acute problem. The slightest uneven pressure, or misalignment of pressure, may cause the resulting product to contain blisters or air pockets which may not readily be discernible when the product is first removed from the press. These faults, or voids, may appear a substantial length of time after the laminating is complete to thereby result in an unsightly product and one that may easily be damaged by merely bumping that portion of the structure having a void or air pocket thus causing the hardwood sheet to chip and crack. Maintaining the appropriate pressure, uniformly distributed over the entire surface of the laminate, and maintaining the appropriate temperature for the cement utilized to bind the veneer to the soft wood support, has become a difficult if not impossible task utilizing prior art laminating presses. Further, prior art laminating presses are unable to cope with short radii of curvature.

Accordingly, it is an object of the present invention to provide a laminating press for use in connection with laminating hardwood sheets to soft wood.

It is also an object of the present invention to provide a laminating press that will exert uniform pressure over a large area of an elongated strip of Wood having curved surfaces such as a door frame.

It is still another object of the present invention to provide a laminating press having a platen temperature control that is readily adjustable while providing uniform pressure over a partially fiat and partially curved surface.

Further objects and advantages of the present invention will become apparent to those skilled in the art as the description thereof proceeds.

Briefly, in accordance with one embodiment of the present invention a laminating press is provided having a platen with a fiat surface inclined at approximately 45 from horizontal. The platen includes a curved portion extending from the lower end of the fiat surface curving upwardly to form a smooth curved continuous surface. The platen is supported on a rigid table that includes a means for adjusting the angle of the inclined surface. An elongated horizontal member, arranged par- Hce a rod and pivot arrangement. The cylinder assembly is, in turn, pivotally attached to the mounting table to which the platen is secured. The cylinder assembly and platen are thus in fixed spaced-apart relationship to permit the cylinder rod extending from the cylinder assembly to force the soft wood and hardwood veneer into intimate contact. The pivotal arrangements of the rod with the elongated horizontal member and the cylinder assembly with the table or platen supporting means provides a floating force to be applied to the laminate. Further, a spring biasing means applies a rotational force to the cylinder assembly forcing the latter about its pivot and urging the corresponding inclined surfaces of the platen and elongated horizontal member into contact.

Thus, a uniform force is applied throughout a laminate and the laminating system is properly registered with the laminate before the pressure is applied. The platen, made from aluminum or steel, acts as an electrical conductor for current applied thereto from a current transformer having a controlled voltage applied to the primary thereof. The combination of correct temperature, reg istration, and uniformity of applied force to the curved and flat surfaces of the laminate yield a void-free veneer on such structures as door frames which heretofore could -not properly be constructed using previously known laminating presses and techniques.

The present invention may more readily be described by reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a laminating press constructedin accordance with the teachings of the present invention.

FIG. 2 is a front elevational view of a portion of the laminating press of FIG. 1.

FIG. 3 is a side view, partially in section, of the laminating press of FIG. 2 taken along line 33.

FIG. 4 is a perspective view of the platen of the laminating press of the present invention.

FIG. 5 is a rear elevational view of the platen of FIG. 1 showing the reinforcing thereof, and schematically showing the electrical circuitry for heating the platen.

FIG. 6 is a side view, in section, showing a modification of the platen of the laminating press of the present invention and the means for adjusting the inclination of the flat surface of the platen.

FIG. 7 is an illustration of a finished hardwood veneered curved laminate useful for understanding the operation of the present invention.

Referring now to FIGS. 1-4, the elongated platen 10 is shown having a fiat surface 11 inclined at approximately 45 from horizontal. The fiat surface 11 is joined by a curved portion 12 extending from the lower end thereof and curving upwardly to form a smooth, curved, continuation'of the flat surface. Thus, the particular curvature shown is intended for use in the manufacture of hardwood veneered door frames of the type described and claimed in the above mentioned co-pending application. It may be noted that both the flat and curved surfaces are to be covered with a thin sheet of hardwood and must therefore have a uniform pressure applied thereto during the laminating operation. The cross-section of the door jam 15 showing soft wood supporting members 16 and 17 and hardwood veneer 18 are clearly shown in FIG. 3, and a perspective view of same may be-seen in FIG. 7.

An elongated horizontal member 20 is provided with an inclined flat surface 21 parallel to the flat surface 11 of the platen. The horizontal member is positioned for vertical movement relative to the platen during which movement the previously mentioned surface 21 thereof will remain parallel to the platen flat surface'at all times. The elongated horizontal member also includes a second fiat surface 25 perpendicular to the first extending therefrom at the lower portion of the member 20. The perpendicularity of the two surfaces of the elongated horizontal member are used to engage the perpendicular surfaces of the soft wood base of the door jam as shown in FIG. 3. The angular relationship of the two surfaces of the elongated horizontal member may vary somewhat in accordance with the application intended for the press;

' further, the two surfaces may be beveled at the intersection thereof to prevent interference of the surfaces from engaging the corresponding surfaces of the soft wood. The laminating press of FIG. 1 shows a pair of platens and corresponding horizontal elongated members. Since each side of the structure of FIG. 1 is identical, the description will be limited to the apparatus shown in the front of FIG. 1.

The elongated horizontal member is provided with a plurality of ears appropriately bored to receive a pivot pin 31 therethrougln Alternatively, conventional pillow blocks may be bolted or otherwise secured to the horizontal member to provide the necessary bearing surfaces for the pivot pin. The pivot pin 31 is positioned so that the axis thereof is horizontal and perpendicular to the axis of the elongated horizontal member and the elongated platen.

A cylinder assembly 35 is secured to the frame 38 of the press through the expediency of supporting arms 39. The supporting arms 39 contain bearings to accept trunnions 40 attached to the cylinder 41 to thereby provide pivotal movement of the cylinder about an axis parallel to the axis of the horizontal member and elongated platen. The cylinder assembly includes a piston 45 and a rod 46 the latter extending vertically downwardly to the pivot pin 31 of the elongated horizontal member. The. pivot pin may join the elongated horizontal member and vertical rod in any convenient pivotal fashion along the pin axis.

A small coil spring 50 is contained within a cylinder 51 and bears against a piston 52 and piston rod 53 urging the latter to extend to the left as shown in FIG. 3. The small cylinder is attached to the laminating press frame 38, and the piston rod is pivotally connected to the upper portion of the cylinder. Force is thus exerted to the left, or counterclockwise as shown in FIG. 3, about the axis of the trunnion 40 to thereby urge the opposing flat inclined surfaces of the elongated horizontal member and platen into engagement. The spring biasing of the cylinder assembly as shown in FIG. 3 insures the proper registration of the elongated horizontal member and the platen prior to the application of laminating pressure. In this manner, misalignment of the horizontal member relative to the platen is prevented and the uneven pressure that would result therefrom is avoided.

To provide structural rigidity, the elongated platen is provided with a plurality of buttresses spaced along the length thereof. The buttresses may readily be seen by reference to FIG. 5 wherein it is shown that the buttresses are spaced evenly along the length of the platen and extend below the platen to keep the curved portion of the platen out of contact from the remainder of the laminating press frame. Also referring to FIG. 5, a schematic illustration of the circuit diagram for controlling the temperature of the platen is shown. A relatively heavy current-carrying cable 61 is secured by welding or the like to each end of the platen. The cable is electrically connected to the secondary winding'62 of a current transformer 63. The primary winding 64 of the current transformer is connected to the secondary of a voltage varying transformer 65 to enable the voltage applied to the, primary of the current transformer to be controlled in accordance with the current requirements for generating heat in the platen. The current transformer 63 and voltage varying transformer 65 may conveniently be mounted on the laminating press frame 38 as shown in 'FIG. 1. The current traveling the length of the platen generates heat .to elevate the temperature of the platen until an equilibrium point is reached and the current flowing through the platen is sufiicient to maintain the temperature at the desired value. The temperature of the platen maybe checked continuously by a conventional thermocouple indicated in FIG. 5.

In the modification shown in FIG. 6, the platen is mounted on reinforcing buttresses 60 as indicated previously in connection with FIG. 5. The buttresses are, in turn, mounted on a pivotal table '72 that may readily be adjusted to pivot about an axis 73 by adjusting bolt 74 to thereby tilt the inclined surface of the platen within a given range. The advantages of the adjustable inclination may be seen when it is considered that the force being applied to the laminate is essentially a vertical downward force being transmitted from the flat surfaces of theelongated horizontal member to the laminate. A division of force between these fiat surfaces will be equal since the flat surface of the platen is inclined at 45 and the pivotal arrangements of the cylinderassem'bly and horizontal elongated member insure complete. alignment of the vertical rodin relationto the force-receiving surfaces of the laminate. Slight variations in the angle of the platen may be made to provide an adjustment to deviate from the division of force provided by the inclination of 45.

The operation of the laminating press of the present invention may be described as follows: A sheet of hardwood veneer is appropriately doped with a suitable cement such as 'a urea resin formaldehyde glue and. placed on the platen with the glue-containing side up. The soft wood base for the laminate is then placed in the platen against the hardwood sheet. Air, under pressure, may then be admitted to the cylinder to force the piston downward and to cause the rod and elongated horizontal member to extend slowly from the cylinder assembly. As the inclined surface of the elongated horizontal member contacts the corresponding surface of the soft wood base, the cylinder assembly is rotated clockwise against the force of the biasing spring. The horizontal member is .thus properly registered relative to the soft wood base. As the piston continues to move downwardly, the elongated horizontal member is forced into intimate and firm contact with the perpendicular surfaces of the soft wood base and forces the latter against the hardwood sheet. The'platen, maintained at an appropriate temperature, receives the laminate which is held firmly in contact therewith and transfers the heat contained therein to the bonding surfaces between the hardwood and soft wood. The angle or inclination of the flat' surface of the platen may be changed to distribute the force exerted by the elongated horizontal member in accordance with the relative areas of the flat and curved surfaces of the laminate.

Thus, through a combination 'of strategic pivotal arrangements, and appropriately applied biasing about one of the pivots, proper registration and uniformity of pressure is achieved by the laminating press of the present invention. While the embodiment chosen for illustration shows three cylinder assemblies uniformly spaced over the length of the elongated horizontal member, it will be understood that one or more cylinder assemblies may be utilized depending on the length of the laminate, the size of the respective cylinders, and the pneumatic pressure available. Further, it is possible to provide an all electric system by substituting electromagnetic solenoids or the like for the cylinder assemblies, and similar electromagnetic devices, of a smaller nature, for the biasing spring means shown in FIG. 3. It is also possible to utilize other means for heating the bonding surface between the hardwood and soft wood. For example, high frequency dielectric heating may take the place of the resistance heating chosen for illustration in the embodiment described. Accordingly, many modifications may be made in the embodiments chosen for illustration without departing from spirit and scope of the present invention.

I claim:

1. A lamina-ting press comprising: a platen having an inclined fiat surface and having a curved portion extending therefrom to form a smooth, curved continuation of said flat surface; a movable member having a fiat inclined surface parallel to the fiat inclined surface of said platen; a force-exerting assembly including a rod; said rod secured to said movable member through a pivotal cou pling having a horizontal axis; means pivotally supporting said force-exerting assembly about a horizontal axis perpendicular to the axis of said pivotal coupling; and mounting means secured to said supporting means and to said platen to maintain a fixed distance between said force exerting assembly and said platen.

2. A laminating press comprising: a platen having a fiat surface inclined at an angle less than 90 from horizontal and having a curved portion extending from the lower end thereof and curving upward to form a smooth, curved continuation of said flat surface; a movable member having a fiat inclined surface parallel to the flat inclined surface of said platen; a cylinder assembly including a piston and a vertically downwardly extending rod secured to said piston; said rod secured to said movable member through a pivotal coupling having a horizontal axis; means pivotally supporting said cylinder about a horizontal axis perpendicular to the axis of said pivotal coupling; and mounting means secured to said supporting means and to said platen to maintain a fixed distance between said cylinder assembly and said platen.

3. A laminating press comprising: a platen having a flat surface inclined at an angle of less than 90 from horizontal and having a curved portion extending from the lower end thereof and curving upward to form a smooth, curved continuation of said flat surface; an elongated horizontal member having a flat surface inclined parallel to the flat surface of said platen; a cylinder assembly including a piston and vertically downwardly extending rod secured to said piston; said rod secured to said elongated horizontal member through a pivotal coupling having a horizontal axis; means pivotally supporting said cylinder assembly about a horizontal axis perpendicular to the axis of said pivotal coupling; and mounting means secured to said supporting means and to said platen to maintain a fixed distance between said cylinder assembly and said platen.

4. A laminating press comprising: a platen having an inclined flat surface and having a curved portion extending from the lower end thereof and curving upward to form a smooth, curved continuation of said fiat surface; an elongated horizontal member having a flat inclined surface parallel to the flat surface of said platen; a cylinder assembly including a piston and vertically downwardly extending rod secured to said piston; said rod secured to said elongated horizontal member through a pivotal coupling having a horizontal axis; trunnion and bearing means pivotally supporting said cylinder assembly about a horizontal axis parallel to the axis of said elongated horizontal member; and mounting means secured to said trunnion and bearing means and to said elongated platen to maintain a fixed distance between said cylinder assembly and said platen.

5. A laminating press comprising: a platen having a flat surface adjustably inclined at an angle less than 90 from horizontal and having a curved portion extending from the lower end thereof and curving upward to form -a smooth, curved continuation of said fiat surface; a movable member having a fiat inclined surface parallel to the fiat inclined surface of said platen; a force-exerting assembly including a rod, said rod secured to said movable member through a pivotal coupling having a horizontal axis; means pivotally supporting said force-exerting assembly about a horizontal axis perpendicular to the axis of said pivotal coupling; marking means secured to said supporting means and to said platen to maintain a fixed 6 distance between said force-exerting assembly and said platen; and means for adjusting the inclination of said flat surface.

6. A laminating press comprising: an elongated platen having a flat surface inclined at 45 and having a curved portion extending from the lower end thereof and curving upward to form a smooth, curved continuation of said flat surface; an elongated horizontal member having a first fiat inclined surface parallel to the flat surface of said platen and having a second fiat surface extending from the lower end of said first surface and perpendicular thereto; a force-exerting assembly including a rod; said rod secured to said elongated horizontal member through. a pivotal coupling having a horizontal axis; means pivotally supporting said force-exerting assembly about a horizontal axis perpendicular to the axis of said pivotal coupling; and mounting means secured to said supporting means and to said platen to maintain a fixed distance between said force-exerting assembly and said platen.

7. A laminating press comprising: an elongated platen having a fiat surface inclined at, 45 and having a curved portion extending from the lower end thereof and curving upward to form a smooth, curved continuation of said flat surface; an elongated horizontal member having a first fiat inclined surface parallel to the fiat surface of said platen and having a second fiat surface extending from the lower end of said first surface and perpendicular thereto; a force-exerting assembly including a rod; said rod secured to said elongated horizontal member through a pivotal coupling having a horizontal axis; trunnion and bearing means pivotally supporting said cylinder assembly about a horizontal axis parallel to the axis of said elongated horizontal member;.and mounting means secured to said trunnion and bearing means and to said elongated platen to maintain a fixedv distance between said cylinder assembly and said platen.

8. A laminating press comprising: a platen having a flat surface inclined at an angle less than from horizontal and having a curved portion extending therefrom; an elongated horizontal member having a flat inclined surface parallel to the flat surface of said platen; a cylinder assembly including a piston and vertically downwardly extending rod secured to said piston; said rod secured to said elongated horizontal member through a pivotal coupling having a horizontal axis perpendicular to the axis of said elongated horizontal member; trunnion and bearing means pivotally supporting said cylinder assembly about a horizontal axis parallel to the axis of said elongated horizontal member; mounting means secured to said trunnion and bearing means and to said elongated platen to maintain a fixed distance between said cylinder assembly and said platen; and spring biasing means connected to said cylinder assembly to force the later to rotate about said trunnion and bearing means in a direction to urge the flat surface of said platen and said horizontal member into contact.

9. A laminating press comprising: a platen having an inclined flat surface and having a curved portion extending therefrom to form a smooth, curved continuation of said fiat surface; a movable member having a fiat inclined surface parallel to the flat inclined surface of said platen; a plurality of cylinder assemblies, each including a piston, and a vertically downwardly extending rod secured to said piston; said rods secured to said movable members through pivotal couplings having horizontal axes; means pivotally supporting said cylinder assemblies about a horizontal axis perpendicular to the axis of said pivotal couplings; and mounting means secured to said supporting means and to said platen to maintain a fixed distance between said cylinder assemblies and said platen.

10. A laminating press comprising: a platen having a flat surface inclined at an angle 45 and having a curved portion extending from the lower end thereof and curving upward to form a smooth, curved continuation of said flat surface; an elongated horizontal member having a flat and a vertically downwardly extending rod secured to said piston; said rods secured to said elongated horizontal member through pivotal couplings having a horizontal axis perpendicular to the axis of said elongated horizontal member; trunnion and bearing means pivotally supporting said cylinder assembliesabout a horizontal axis parallel to force the latter to rotate about aid trunnion and bearing means in a direction to urge the flat surface of said platen and the horizontal member into contact.

11. The apparatus defined in claim 3 wherein said cylin- I der assembly includes a pneumatic cylinder and including means for applying pneumatic pressure to said pneumatic cylinder to force said piston rod downward.

12. The apparatus defined in claim 9 wherein said plurality of cylinder assemblies each include pneumatic cylinders and means for applying pneumatic pressure to said pneumatic cylinders to force said piston rods downward.

13. A laminating press comprising: a platen having an inclined flat surface and having a curved portion extending therefrom to form a smooth, curved continuation of said flat surface; means for controllably heating said platen; a movable member having a flat inclined surface parallel to the flat inclined surface of said platen; a forceextending assembly including a rod; said rod secured to said movable member through a pivotal coupling having a horizontal axis; means piwotally supporting said forceexerting assembly about a horizontal axis perpendicular to the axis of said pivotal coupling; and mounting means secured to said supporting means and to said platen to maintain a fixed distance between said force-exerting assembly and said platen.

14. A laminating press comprising: a platen having a flat surface inclined at an angle of less than 90 from horizontal and having a curved portion extending from the lower end thereof and cunving upward to form a smooth, curved continuation of said flat surface; means for controllably heating said platen; an elongated horizontal member having a flat surface inclined parallel to the fiat surface of said platen; a cylinder assembly including a piston and vertically downwardly extending rod secured to said elongated horizontal member through a pivotal coupling having a horizontal axis; means pivotally supporting said cylinder assembly about a horizontal axis perpendicular to the axis of said pivotal coupling; and mounting means secured to said supporting means and to said platen to maintain a fixed distance between said cylinder assembly and said platen.

15. A laminating press comprising: an elongated platen having a flat surface inclined at and having a curved portion extending from the lower end thereof and curving upward to form a smooth, cunved continuation of said flat surface; means for controllably heating said platen; an elongated horizontal member having a first flat inclined surface parallel to the flat surface of said platen and having a second fiat surface extending from the lower end of said first surface and perpendicular thereto; a forceexerting assembly including a rod; said rod secured to said elongated horizontal member through a pivotal coupling having a horizontal axis; trunnion and bearing means pivotally supporting said cylinder assembly about a horizontal axis parallelto the axis of said elongated horizontal member; and mounting means secured to said trunnion and bearing means and to said elongated platen to maintain a fixed distance between said cylinder assembly and said platen.

No references cited.

WILLIAM W. DYER, IR., Primary Examiner.

RALPH Z. ZLOTNIK, Assistant Examiner. 

1. A LAMINATING PRESS COMPRISING: A PLATEN HAVING AN INCLINED FLAT SURFACE AND HAVING A CURVED PORTION EXTENDING THEREFROM TO FORM A SMOOTH, CURVED CONTINUATION OF SAID FLAT SURFACE; A MOVABLE MEMBER HAVING A FLAT INCLINED SURFACE PARALLEL TO THE FLAT INCLINED SURFACE OF SAID PLATEN; A FORCE-EXERTING ASSEMBLY INCLUDING A ROD; SAID ROD SECURED TO SAID MOVABLE MEMBER THROUGH A PIVOTAL COUPLING HAVING A HORIZONTAL AXIS; MEANS PIVOTALLY SUPPORTING SAID FORCE-EXERTING ASSEMBLY ABOUT A HORIZONTAL AXIS PERPENDICULAR TO THE AXIS OF SAID PIVOTAL COUPLING; AND MOUNTING MEANS SECURED TO SAID SUPPORTING MEANS AND TO SAID PLATEN TO MAINTAIN A FIXED DISTANCE BETWEEN SAID FORCEEXERTING ASSEMBLY AND SAID PLATEN. 